This invention relates to abrasive bodies.
Abrasive compacts are well known in the art and are used extensively in industry for the abrading of various workpieces. They consist essentially of a mass of abrasive particles present in an amount of at least 70 percent, preferably 80 to 90 percent, by volume of the compact bonded into a hard conglomerate. Compacts are polycrystalline masses having some direct diamond-to-diamond bonding. The abrasive particles of compacts are invariably super-hard abrasives such as diamond and cubic boron nitride.
Abrasive compacts may contain a second phase or bonding matrix which contains a catalyst (also known as a solvent) useful in synthesising the particles. In the case of cubic boron nitride examples of suitable catalysts are aluminium or an alloy of aluminium with nickel, cobalt, iron, manganese or chromium. In the case of diamond, examples of suitable catalysts are metals of Group VIII of the Periodic Table such as cobalt, nickel or iron or an alloy containing such a metal.
Abrasive compacts may be provided in the form of circular discs or segments thereof or fragments of other shapes.
Diamond and cubic boron nitride compacts are manufactured under conditions of temperature and pressure at which the abrasive particle is crystallographically stable.
Abrasive compacts may be bonded directly to a tool or shank for use. Alternatively, they may be bonded to a backing such as a cemented carbide backing prior to being mounted on a tool or shank. Abrasive compacts bonded to a backing, typically a cemented carbide backing, are also known as "composite abrasive compacts".
Examples of abrasive compacts and composite abrasive compacts can be found in many patent specifications, e.g. British Patent Specification Nos. 1,489,130; 1,456,765 and 2048927 and U.S. Pat. specifications Nos. 3,745,623; 3,743,489 and 4,224,380.